ExMark stops running intermittently.

[Badbart]

For a year now our Lazer Z with a Kawasaki FX801V motor will try and stall out after running 10-15 minutes. I can slowly advance the choke to keep it running and after a few minutes it will usually return to normal full throttle running. Or if it does stall out completely, it can be restarted and run fine for some period of time until it starts this stalling out procedure all over again.Of note, it does not miss, motor was tuned up last fall and has new plugs, fuel and air filter. It also does not have a vented fuel cap. None of these things being changed has fixed the problem. I've seen other forums with almost the same issue, but so far no real solution that I can find. Any good ideas?

 

[MF2604h]

I also have a exmark lazer z with the Kawasaki engine, and a Ferris with a Kawasaki engine.
Both did the same thing yours is doing. It’s a simple fix take the in-line fuel filter off and put a bigger one on. The fuel filter from the factory is not big enough to let enough fuel through.
I was so pissed off with my Ferris doing that, that I just about put a match in the gas tank and claimed it on insurance. I took it to my dealer, and he said he sees it all the time with the Kawasaki engine. He put a Kohler filter on it, and it’s never done it again.
I took the exmark to my dealer, and told them what is was doing. The mechanic said everything was working fine. I told him to change the fuel filter. He changed it to a bigger one, and so far no more problems. Once he took the original filter off he even said it was awfully small for that engine.
Hopefully this helps and solves your problem.

 

[RandyT]

It isn't so much a too small fuel filter because I am sure the filter that is being used on the Kawasaki engines from the factories has enough volume. the problem is that filter can't pass enough fuel while operating under a slight vacuum due to emissions control devices.

 

[PuffyC]

You'd think they would design their product to function properly with a right-sized fuel filter but who knows. I will say that I had a mower behave this same way and it was a dirty carb. It would run for a bit but then start to die, and if I hit the fuel bulb it would run fine for a while before doing it again. That, like the choke, pretty much tells you it's a fuel problem, so maybe the fuel filter is marginal to start with, and when combined with some gunk in the carb or some dicey gas it all works together to slowly starve the engine. But that's just a WAG - I'd love to hear what it turns out to be.

 

[clinter36]

I had the same problem on a Kawasaki powered zero turn. Once it was a clear slime that clogged the fuel filter. Another time it was the fuel pump (I figured that out after assuming it was the filter again). And... in fact I had to replace the pump 2x because the cheap pump I bought the first time was faulty. Buy the OEM pump and save yourself the torment.

 

[5030]

While not directly on subject, when was the last time you adjusted the valves? Kowalski's are extremely sensitive to valve lash but super easy to adjust....and.. Kowalski's have the ignition trigger wire affixed to the intake manifold when it tends to rub and eventually short out. I slipped a length of fuel hose over mine and zip tied that to the manifold. I have around 700 hours on mine in my zero turn and it's really been a dependable motor. My wife has the Kohler on her zero turn and it's an oil burner. Least I don't have to change it, I just keep adding......